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    flg = false;
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    let str1 = '君子坦荡荡，小人常戚戚'
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    //君子坦荡荡，小人常戚戚
    let str2 = 'he said：\'forever\'';
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    str2 = "子曰：\"君子坦荡荡，小人常戚戚\"";
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